Sobreposição de atividade entre dois mesopredadores simpátricos, jaguatirica (Leopardus pardalis) e irara (Eira barbara), na reserva ecológica de Maracá

Abstract

Predator-prey interactions are a focus in ecology and conservation due to their importance as a key structuring mechanism in biotic communities. To provide a baseline reference for conservation planning, it is important to understand how carnivores interact with their prey and competitors in areas that do not experience direct anthropogenic impacts. In this study, we investigated the temporal activity patterns of the Ocelot (Leopardus pardalis) and Tayra (Eira barbara) and their prey on a large, protected island in Brazilian Amazonia. Using photographs taken by camera-traps over two and a half years (2018-2020), we assessed the patterns of temporal overlap and separation between both carnivore species and multiple mammal and bird prey species. We estimated activity patterns using kernel density and measured the overlap between estimated paired distributions using an overlap coefficient. Using time differences between co-occurrences, we tested predictions that Tayra and Ocelot would appear less frequently at locations previously visited by the other species, and more frequently at locations previously visited by their prey. The temporal overlap between predators was lower (Δ = 0.35) than with their prey (Δ = 0.58 – 0.84 and Δ = 0.66 – 0.73 for Tayra and Ocelot respectively). There was no evidence of changes in activity between cameras with or without both carnivores. Indeed, we found more than double the number of images of Tayra at camera-traps that also had Ocelots. The subordinate Tayra appeared to avoid locations with Ocelot by at least 24 hours, whereas there were no apparent differences in the frequency of Ocelot images before or after Tayra. The results provide the first insight into temporal interactions involving sympatric carnivores and their potential prey on an Amazonian island. In general, our results suggest that Tayra may tailor their activity daily to maintain temporal separation from Ocelots. Future studies should address the poorly documented patterns across vertical forest strata for these partially arboreal carnivores.